<!DOCTYPE html>
<html lang="en">

<head>
  <meta charset="UTF-8">
  <meta http-equiv="X-UA-Compatible" content="IE=edge">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>Document</title>
</head>

<body>
  <script>
    // = 赋值运算符
    var num = 123
    // 链式赋值 从右往左
    var num1 = num2 = num3 = 321
    console.log(num1, num2, num3)

    var a, b, c
    a = b = c = 2 + 2 // 4
    console.log(a, b, c)

  </script>
</body>

</html>